A telephone network generally consists of a plurality of separate telephone exchanges connected to each other via transmission lines. The telephone network is managed and maintained via an operation and maintenance network (O&M-network), which can be implemented e.g. on the basis of the services of an X.25 packet network. The operation and maintenance network is created by connecting to it the telephone exchanges and other network components to be controlled. The other network components to be controlled include e.g. the transcoder (TC), base transceiver station (BTS) and base station controller (BSC). The functions for operating the telephone network are mainly concentrated in control rooms and in network elements centralizing operation and maintenance functions. An example of centralizing network elements like this is the DX 200 OMC manufactured by Nokia.
From centralizing telephone network elements, it is possible to set up remote session connections to other telephone exchanges or telephone switching systems. When a remote session is established, the source system, i.e. e.g. a centralizing network element, sends user identification data, a user identification code and a password, to the target system. The target system is e.g. a telephone switching system.
In the DX 200 telephone switching system and in the user interface (Man Machine Interface, MMI) of the operation and maintenance network, the user's authority and rights are determined on the basis of the user identification (user ID). The MMI system is a certain aggregate of peripherals and software which can be used to execute operation and maintenance functions. For each user ID, an individual password has been defined for the verification of authenticity of the user. To minimize the data security risks, it is necessary to change the password frequently enough to ensure that a person not authorized to use a user ID will not be able to utilize a user ID not belonging to him/her.
In the above-mentioned system, the problem is that different network elements may have different versions of password encryption software. At present, user identification on a remote connection is so implemented that, if the software versions in the source system and in the remote system differ from each other, the user must enter the required password again when the remote session is started.
The object of the present invention is to eliminate the drawbacks referred to above or at least to significantly alleviate them.
A specific object of the invention is to disclose a new type of method and system which will obviate the need for re-input of a password, thus improving the convenience of use from the user's point of view.
As for the features characteristic of the present invention, reference is made to the claims.